ANNOYING door - hard to lock!

[shortrackskater]

This happened in my Fortune One but could happen in any older slot.
My Fortune One was always tight closing. It takes a hard turn of the key to lock the door. Two nights ago, the key finally broke off IN the lock. Luckily, the door was not fully latched!
The first thing I did was manually turn the tab so the lock was in position for the piece of the key to come out, since the OPEN position keeps the key locked in I believe.
I got it out using my "pokey" metal tool (with curved ends for spring removal and placement) and needle nosed tweezers.
My question IS:
HOW THE HECK can I make this door open and close easily? I've checked the door alignment. I've removed the channel on the door and made sure it was straight...everywhere. I've closely examined the "hook catch" piece on the cabinet part. It's perfectly straight and the hooks that come out to catch the channel on the door are perfectly straight . None are squeezed in or deformed in any way. There no reason why this stupid door shouldn't close easily. 
I'm already bending the new key now so, for the time being, I think I'll replace the lock again with a round key.
ANY IDEAS???

[4 Deuces]

Hey, on my game kings, I had to adjust the rod in the door that the door lock in the machine latches onto.  Now, I can gently close the door and the latch automatically catches without having to push the door harder or push the latch handle back.  I don't have a F1, but I would think you could adjust that door latch?  I read that you tried several ways.  The only other thing I can think of is the lock rod is too short, so the cam has trouble crossing over the latch?  Maybe a longer lock will ease it up?
 

Good luck with this one!

:Dave

[cowboygames]

You might try using a dremel tool to make the notch in the hook catch a little wider

[rickhunter]

I use a little wd40 applied anywhere there two pieces of metal latch together for the close.  My mother's S2000 was a hard close and ever since I did this, it closes like a hot knife through butter.

[shortrackskater]

Thanks everyone. I will try these things! I don't have a dremel but I have a nice file!